Just tested my new 2016 at three different temps including 10 degrees and it fired up no problem. Here's the video: https://www.youtube.com/watch?v=b4wEVcSPepQ

 

Your 2016 Rancher is efi, the original poster most likely had an older carb 350. I had a 350 as well and it was easier to start than my carb Grizzly 660 I have now. The one advantage to the 350 was that it was easy to pull start, I'd hate to have to pull start the Grizzly. The 350 doesn't have a primer button that I'm aware of, not sure about the older 300. I think my grizzly battery is a little weak, I'm going to take it out and charge it to give it a full charge this week. i just started and ran it a little yesterday and it took a bit of effort. Once you get it started, you have to let it idle for a min or 2(with the choke pulled fully out) when cold or it will die too. Once warmed up, it runs great. The idle might need to be adjusted as well but its never failed to start yet.

 

A Honda 300 with a clean carb will start instantly without choke, unless the temp is very low. A Honda 350 will start OK with choke in winter and without choke in summer. The newer, EFI models start well, as long as you don't touch the throttle until after they have fired up. All the CD carbed models had a prime button in the float chamber and most, post circa 2000 had a heater "thingy" as well.

 

I've noticed that on most quads, the longer you let them sit, the harder they are to start. My Grizzly had sat for about 2 weeks and that's why it took a bit longer to start. Still had it started within about 2-3 min. Went out the next day and it started instantly as soon as I pulled the choke and hit the starter button. Still needed to let it warm up about a minute with the choke on before it would idle smoothly without the choke. Once it is warmed up, it runs great. My Rancher 350 was about the same. I think the choke never worked properly on it so I would just give it a moderate amount of throttle off and on to simulate what the choke would do to warm it up for a minute or so and then it would smooth out.

 

Yep. I never hit the throttle, just hit the starter and it goes every time, every elevation, every temperature. I love EFI.